What’s the Difference Between Acrylic Sheets, Plexiglass, Polyurethane Sheet, and PEEK Plastic?

2025-10-08 11:15:55

　　Walk into any plastics supplier, and you’ll be met with a dizzying array of options. Among them, Acrylic, plexiglass, polyurethane, and PEEK are common names that often pop up. While they might all fall under the broad category of “plastic sheets,” using them interchangeably is a recipe for disappointment. Their properties, costs, and ideal applications are worlds apart. This guide will serve as your roadmap to understanding these key materials, starting with the most common mix-up of all.

　　Let’s get this out of the way first: Plexiglass is acrylic. The term "Plexiglass" is a brand name, much like "Band-Aid" is for adhesive bandages. The actual material is called Polymethyl Methacrylate (PMMA), universally known as Acrylic sheet. So, when you're comparing Plexiglass to acrylic, you're comparing a brand to the material itself. For the sake of clarity, we'll use the term "acrylic" from here on.

　　Acrylic Sheet: The Champion of Clarity and Value

　　Imagine a material that is clearer than glass, significantly lighter, and far more shatter-resistant. That's acrylic. Its primary superpowers are its brilliant optical clarity and excellent resistance to weathering and UV rays, meaning it won’t yellow or degrade in sunlight. This combination of transparency and durability makes it the undisputed choice for applications like storefront signage, protective barriers, display cases, and greenhouse windows. It’s also relatively easy to work with using standard woodworking tools. If your project needs to see and be seen, all while staying within a reasonable budget, acrylic is your go-to material.

　　Polyurethane Sheet: The Unseen Guardian of Industry

　　While acrylic is the star of the show in display applications, polyurethane is the unsung hero on the factory floor. Don’t let its sometimes less-sparkly appearance fool you; this material is built for punishment. Its defining characteristic is an almost legendary resistance to impact, abrasion, and tearing. Where acrylic might scratch or crack, polyurethane simply absorbs the abuse. This makes it the perfect material for demanding roles like lining mining chutes, serving as a self-lubricating bearing surface, protecting machinery as a robust guard, or functioning as a long-lasting conveyor belt component. Think of polyurethane as your first line of defense in high-wear, high-impact environments.

　　PEEK Plastic: The Engineering Marvel for Extreme Environments

　　Then there is PEEK, a material that operates in a different league altogether. Polyether Ether Ketone (PEEK) is a high-performance thermoplastic that laughs in the face of conditions that would melt, crack, or corrode other plastics. Its most staggering property is its ability to perform continuously at temperatures high enough to make most other plastics droop or decompose—up to 480°F (250°C). Couple that with incredible mechanical strength, inherent flame resistance, and superb resistance to a vast range of chemicals, and you have a true engineering superstar. Unsurprisingly, this top-tier performance commands a top-tier price. PEEK is reserved for the most critical applications: medical implants inside the human body, components in jet engines, and parts in aggressive chemical processing equipment.

　　Navigating Your Material Selection

　　Choosing between these materials boils down to a simple assessment of your project's primary challenge. Let your key requirement guide you:

　　Is it visual appeal and outdoor exposure? The clear winner is Acrylic.

　　Is it physical abuse, impact, and constant wear? You need the toughness of Polyurethane.

　　Is it extreme heat, harsh chemicals, or mission-critical performance? Nothing less than PEEK will do.

　　By aligning your needs with the inherent strengths of each plastic, you move from guessing to making an informed, confident decision. Understanding these differences ensures your project is built on a foundation of success, not a compromise that could lead to failure.